A rectangle has a width of $3$ units. The rectangle's length is $5$ times its width. What is the area of the rectangle?
Explanation: Area is the amount of space a flat shape fills. $\text{Area of a rectangle} = \text{width} \times \text{length}$ The ${\text{ width}}$ is ${3}\text{ units}$ and the ${\text{length}}$ is $5$ times the ${\text{width}}$. $5\times3\text{ units}$ $5\times3\text{ units}$ $$ $\,3\text{ units}$ $\,3\text{ units}$ The ${\text{length}}$ is $5\times3={15}$ units. $15\text{ units}$ $15\text{ units}$ $$ $\,3\text{ units}$ $\,3\text{ units}$ Now, we can find the area. $\begin{aligned} {\text{Area}} &= {l} \times {w}\\\\ &= {15}\times {3}\\\\ &=45 \end{aligned}$ The area of the rectangle is $45$ square units.